Clamp operating apparatus



a my 1 c. SEYBOLD 2,23,75

CLAMP OPERATING APPARATUS Filed Aug. '7, 1955 3 Sheets-Sheet 2 INVENTOR. CHAIFL as 621 50; 0.

3 BY wm w ATTORNEYS.

- y 1935. c. SEYBOLD 2,623,75

CLAMP OPERATING APPARATUS Filed Aug. 7, 1955 5 Sheets-Sheet 5 INVENTOR. HAIPLE$ SEYEOLD,

ATTORNEYS.

Patented Dec. 10, 1935 UNITED STATES PATENT OFFICE 2,023,795 CLAMP OPERATING: APPARATUS Charles Seybold, Oakwood', Ohio Application August 7, 1935, Serial No. 35,160

11 Claims.

My invention relates to apparatus used to operate clamps for holding stacks of material during a cutting operation on a power cutting machine, and is an improvement upon the mechanism disclosed and claimed in my co-pending application Ser. No. 661,595, filed March 18, 1933.

In my co-pending application aforementioned, means were provided whereby the system of levers moved as a unit until the clamp bar came into 1 contact with the material to be clamped... At this point the resistance offered by the material to be clamped caused a change in the operation of the mechanism and the axis of oscillation was shifted to another point. The new axis of oscillation was on a movable link whereby when great pressure was exerted on the system considerable chattering resulted.

It is therefore an object of the present invention to provide means for locking that portion of the system which bears the new pivot point whereby such chattering is eliminated.

It is further an object of my invention to provide a more smoothly working mechanism for the purpose described and one which will exert a standard amount of pressure on the work to be clamped regardless of the thickness of the latter.

Generally it is an object of my invention to provide a mechanism for clamping sheets in 30 which a clamp bar is rapidly approached to clamping position and in which, after clamping position has been attained, a large amount of pressure is resiliently exerted upon the sheets. It is another object of my invention to provide a clamping mechanism as above described in which the clamping means become effective upon contact of the clamp bar with the work regardless of the height of the work to be clamped.

These and other objects will be more specifi- 40 cally pointed out in the specifications and drawings illustrating my device in its preferred form. In the drawings:

Figure 1 is a perspective of a cutting machine.

Fig. 2 is' a partial sectional side elevation of the mechanism as seen from the right in Fig. 1, In this view the parts are shown in the position which they occupy at the beginning of the clamping operation.

Fig. 3 is a rear shown in Fig. 2.

Fig. 4 is a view similar to Fig. 2 except that the parts are shown in the position which they occupy at the end of theclamping stroke.

Fig. 5- is a detailed view of the uppermember.

elevation of the mechanism hinge (CI.v 164-51) Referring to Fig; 1 I have shown the basev I, which carries a cutting table Ia and from which extend the vertical cutter blade guides 2 and 2a in which the cutter 3- is slidable. The cutter blade is actuated by the pull rods 4 and 4a which 5 are fastened to thecutter blade by means of the clevises 5 and 511. At its lower ends the pull rod 4- is attached by means of the clevis 8 to a crank 9 which is fixed upon the shaft Ill. The other end of the shaft It carries a bull wheel l2 and 10 the pull rod 4a is attached by means of a clevis 8a to a crank 9 on the said bull wheel. The shaft 3- rotates in the bearings l3, l'3a and 1312. At the rear of the machine is a jack shaft it whichhas at one end a gear (not shown) which meshes with the teeth l5 of the bull wheel 12.

At l-B- I have shown an eccentric disc which is mounted upon the shaft Ill. The yokes ilia surround this eccentric disc and are fastened together by the bolts 16b. One of the said yokes bears a boss 11 which is threaded to receive a threaded end of the push rod 18 and a lock nut lad is provided to fixthe positionof the push rod 18. The other end of the push rod 18 is threaded into a boss l9 on the collar it which collar 2t]- carries a pin 2| which connects it with the cam member 22.

This cammember 22 is mounted on a fixed shaft 23 which is mounted in bearings 23a on the standards 23b which are fixed to the base i by means of the bolts 23c. The cam member 22 is provided with a partially circular cam surface 22a and a hook portion 221). This hook portion in connection with the cam surface forms a notch 220 for purposes which will be described hereinafter. Loosely mounted upon the shaft 23 are the washers 24. Pins 25 are screwed into the said washers and a bar 26 is slidably mounted on these twopins 25. Compression springs 21 are held on these pins by washers 28 and lock nuts 29-. The springs 21 thus bear against the washers 28 and tend to force the bar 26 toward the left as seen in Fig. 2'. The upper arms of a double bell-crank as are screwed to the bar 2% by means of the screws 3011.

Also mounted upon the fixed shaft 23 are the members 3| having elongated holes 3la. The shaft 23 extends through these holes Sla and the members 31 are thus capable of both oscillatory and reciprocal motion. At their upper endsthemembers Bl are provided with spring cups 31c which carry the compression springs 31b. These springs 31b bear against the washers Me which are adjustable by means of the studs 7, 3ld. The other ends of the springs 3m bear 55 against the washers 24. The purpose of this construction is to maintain the members 3| in the position shown in Fig. 2. A pin 32 connects the lower ends of the members 3| and is pinned to each of the members 3| by the pins 32a. The pin 32 at its center carries the compound wedge block 33 which is fixed to the pin 32 by means of the pin 32b. At 34 I have shown an arcuate compound wedge shoe which is fastened to an arcuate frame 34a by means of the bolts. 340. The frame 34a is fastened to the base of the machine by the bolts 3%.

Also extending across between the members 3| is a pivot pin 35 which is pinned to the respective members 3| by the pins 35a. The double bell-crank 30 is mounted on the pin 35 and carries at the ends of its lower arms the bosses 30b. Connecting the upper arms of the double bellcrank is the pin 300 which carries the roller 306 which is of a diameter to fit the notch 220 in the cam member 22. These bosses are provided with slots 3012.

Also pivoted on the shaft 23 are the upper hinges 36 which are shown in detail in Fig. 5. The upper hinges 33 have enlarged portions 3611 within which the upper ends of the springs 42 are retained and at their other ends have extensions 33b which carry the pins 31. The lower hinge members are shown at 33 and have extensions 3311 which carry pins 38b which ride in the slots 3001 on the lower ends of the double bellcrank 30. These upper and lower hinge members have two holes 39, respectively, and the holes 39 and the lower hinge members have a square counterbore 39a to accommodate the heads of the bolts 40a which extend through the aligned holes 33. At their threaded ends the bolts 49 are provided with washers 43b and lock nuts 400. Each of the upper and lower hinge members has spring cups 4| and the heavy compression springs 42 have their upper and lower ends, respectively, retained in these spring cups. The upper ends of the springs 42 bear against washers 43 the position of which is adjustable by means of the screws 44 which are threaded into the bosses 44a and locked by means of the lock nuts 44b. The upper hingemembers 36 also carry pins 45 and bars 46 connect the pins 45 with the levers 48 at the pins 41. The levers 48 are carried on a shaft 49 carried in the side walls of the housing, and this shaft also carries the levers 50 which connect with the pull rods 52 at 5|.

Operation After placing a stack of material in position for a cut the operator stepson a foot treadle to set the bull wheel'and shaft l0 into rotation. While the shaft is rotated the clamp and knife will both move down, the clamp being timed to be in advance of the knife so as to apply pressure and compression and hold the material before the knife begins to cut.

The eccentric is the prime mover for the clamp mechanism. As the eccentric moves from the position shown in Fig. 2 the rod I8 is pushed to the right. This causes an oscillation of the cam member 22 in a clockwise direction. As long as the movement of the clamp bar is not resisted by the material to be clamped the spring 27 will urge the bar 26 toward the left thus pressing the roller 3||e into its notch 220. Thus the whole system including the members 3| and the hinge members will be oscillated in a clockwise direction about the shaft 23 without relative movement of its parts.

As soon as the clamp bar encounters the material which is to be clamped the compression of the spring 21 is overcome and the double bellcrank 30 will be caused to rotate slightly in a clockwise direction about the pivot 38b by reason 5 of the rise of the cam 22a. The result is that the pin 35 forces the members 3| downward against the compression of the springs 3| b and causes the compound wedge block 33 to wedge against the shoe 34. It is to be understood that at the 10 time this movement occurs the whole system has oscillated somewhat about its axis so that the members 3| are in the position shown in Fig. 4.

Now with the members 3| firmly locked any further movement of the push rod 8 through 15 the cam member 22 causes a clockwise turning of the double bell-crank 33 about the pin 35 which now forms a fixed pivot. This relative movement of the parts puts a pressure on the springs 42 causing a clockwise rotation of the 20 upper hinge members 36 about the shaft 23. This has the eifect of moving the pins 45 toward the left and causes a counter clockwise movement of the members 48 and 50 thereby exerting a pull on the pull rods 52. It is to be noted that 25 when the lower ends of the members 36' move toward the left the lower hinge members 38 are caused to move to the left and it is for this reason that the slots 30d are provided in the lower arms of the double bell-crank 3B. 30

When the cutter has completed its out and the eccentric tends to return the system to its original position the pull on the rod i8 causes a counter clockwise movement of the cam member 22 the hook portion 22b of which exerts an 35 upward pull on the double bell-crank 33 thereby releasing the compound wedge block 33 from its shoe 34. The action of the various compression springs then immediately returns to the system to the position shown in Fig. 2.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:

1. A transmission mechanism comprising a shaft and a system of levers adapted to oscillate therein as a unit without relative movement of the members, means actuated upon a predetermined degree of resistance to said oscillation to look a portion of said system against oscillation thereby causing a relative movement of the members for the purposes described, said means comprising a shaft, a first lever oscillatable upon said shaft, a

wedging member oscillatable and reciprocable upon said shaft, a wedging surface with which 55 said wedging member is adapted to be engaged, and a second lever oscillatable upon said wedging member and having a resilient latching engagement with a portion of said first lever.

I 2. A mechanism for transmitting a uniform 60 linear force from a motive means to a clamp means in two phases, the first at relatively high speed and low power, and the second at relatively low speed but with a great amount of power, comprising a shaft, a first lever oscillatable on said 5 shaft, a link oscillatable and reciprocable on said shaft and a second lever oscillatable on said link but having a resilient latching engagement with said first lever, said whole system adapted to oscillate about said shaft without relative movement 70 of the parts, means actuated by a predetermined resistance to said oscillation to prevent further oscillation of said link and to cause oscillation of said second lever relative to said link and said 3. Clamp mechanism comprising a clamp, a shaft, a lever oscillatable about said shaft and a wedging member oscillatable and reciprocable on said shaft and a wedging surface with which said wedging member may engage, a second lever oscillatable on said wedging member and having a resilient latched engagement with said first mentioned lever whereby said entire mechanism oscillates as a unit about said shaft, a link mechanism actuated by said second lever and including reactionary means, to actuate said clamp and motive means to actuate said first mentioned lever, said second lever adapted to be displaced from said latching engagement upon resistance to the clamp, to force said wedging member against said surface, said second lever then transmitting power from said motive means to said clamp through said reactionary means by oscillation about its mounting on said Wedging member.

4. Clamp mechanism comprising a clamp, a shaft, a first lever having a latching portion and adjacent cam means, oscillatable upon said shaft, a wedging member oscillatable and reciprocable on said shaft and a wedging surface with which said wedging member is adapted to engage, a second lever oscillatable on saidwedging member and having a resilient latched engagement with the latching portion of said first lever whereby said entire mechanism oscillates as .a unit upon said shaft, a link mechanism including reactionary means actuated by said second lever to actuate said clamp and motive means to actuate said first lever, said second lever adapted, upon resistance to the clamp, to be displaced from said latching engagement thereby forcing said wedging member against said surface, said second lever then being adapted to be further actuated by said cam means to transmit power from said motive means to said clamp through said reactionary means by oscillation about its mounting on said wedged wedging member.

5. In a clamp, for the purpose described, a lever system connected to the clamp and initially movable as a unit, said lever system including as part thereof relatively movable members, one of which is a cam, another a heavy compression spring, and another a member to engage the cam, connection from said relatively movable members to the clamp, and means for locking the system frem moving as a unit upon initial building up of pressure by the clamp, whereby the relatively movable members will act to apply heavy pressure through the spring.

6. In a clamp for the purpose described, a lever system connected to the clamp and to an actuating member, said system spring held to operate as a unit on a single axis until initial pressure is developed by the clamp, the portion of said system connected to the clamp and the portion connected to the operating member, arranged ior relative movement with respect to each other, and means for locking the lever system against unit movement upon giving way of the spring which holds it together under initial pressure, whereby the system portions named will move relatively to each other applying heavy pres- 5 sure.

7. In a clamp for the purpose described, a lever system connected to the clamp and to an actuating member, said system spring held to operate as a unit on a single axis until initial pressure is developed by the clamp, the portion of said system connected to the clamp and the portion connected to the operating member, arranged for relative movement with respect to each other, and means for locking the lever system against unit movement upon giving way of the spring which holds it together under initial pressure, whereby the system portions named will move relatively to each other applying heavy pressure, said system portions having means transmitting power from one to the other including a cam on one member, and a compression spring through which the cam movement is applied.

8. In a clamping device an actuating means, a clamp, and a transmission system between them including a compression spring, the system arranged so that the spring is not compressed until the system has applied initial pressure to the clamp, said system arranged to operate as a unit until said initial pressure has been applied, and means to lock it against movement as a unit when same has been applied.

9. A poweroperated device for applying a clamp including a series of levels, a spring and a cam, said device arranged to pivot about a single axis, said spring normally preventing movement of the cam, so long as the device is free to move as a unit, and means for locking the system against movement on said single axis when the cam movement begins.

10. A power operated device for applying a clamp including a series of levers, .a spring and a cam, said device arranged to pivot about a single axis, said spring normally preventing movement of the cam, so long as the device is free to move as a unit, and means operated by the cam for locking the system against movement on said single axis when the cam movement begins.

11. In combination with a clamp, transmission means to apply power to the clamp comprising a spring reactive means forming an intermediate part of said transmission means and through which force is applied to the clamp, and a sliding connection forming an intermediate part or said transmission means for applying pressure to said spring reactive means, and means adapted, upon actuation of said sliding connection, to lock said transmission means, exclusive of said spring reactive means and said connection.

CHARLES SEYBOLD. 

